Assessment of the Carbon Pool at ProNamib Nature Reserve (PNNR),

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Date

2023-09

Journal Title

Journal ISSN

Volume Title

Publisher

Namibia University of Science and Technology

Abstract

Climate change in many African regions, including Namibia, is projected to get worse in the coming decennia. The consequences will mostly affect communities living in rural areas (especially in semi-arid and arid areas) as they depend on agriculture for livelihood. Poor land uses combined with drought, flood or low precipitation can eventually lead to hunger and a collapsed economy. But it is believed that global drylands have the potential to sequester carbon of about 1000 teragram (1000 Tg C yrꟷ¹), if the dryland soil and biodiversity are restored. This study took place in the ProNamib Nature Reserve (PNNR) and neighbouring livestock farms (Eckberg and Houmoed). The area is semi-arid with localised rainfall. The study’s objectives were to define the appropriate methods for determining the carbon stock in arid environments; to map and investigate the spatial pattern of the carbon stock at PNNR (ProNamib Nature Reserve) and compare that with the neighbouring livestock farm, and lastly; to investigate the key drivers of the carbon stock at PNNR and compare that with the neighbouring livestock farm. Carbon in drylands is found in different carbon pools, namely: vegetation (woody plants and herbaceous), soil and litter. We assessed carbon stock in three carbon pools (woody plants, herbaceous vegetation and soil). The study area was divided into three land management units, based on prior and current land uses (livestock farming abandoned in 2018, abandoned in 2000 and current livestock farming), and further stratified into habitats (river, mountain and grassplain). Data were collected using a stratified random sampling method in QGIS. Each management unit was allocated 30 sampling plots (ten per habitat), which totalled up to 90 sampling plots. The plots were 500m² in size for woody species, four one m² quadrats for herbaceous species and soil was collected at the centre of each plot up to a 30cm depth. Allometric equations were used to estimate the aboveground and belowground woody carbon stock. Herbaceous dry biomass was weighted, while the soil was analysed with the dry combustion/LOI method in the soil lab. These are among the methods that many researchers favour the most based on literature review. This study concluded that the soil carbon pool stores 90% of the carbon in the ProNamib area. The highest total carbon stock among habitats is recorded in the mountain (22 tonnes ha¯¹). In terms of management units, the ‘’livestock’’ unit has the highest carbon stock in the area (21 tonnes ha¯¹), the second highest is recorded in the ‘’abandoned in 2018’’ unit (18 tonnes ha¯¹), while the lowest carbon stock in the area is found in the ‘’abandoned in 2000’’ with 16 tonnes ha¯¹. This study serves as a pilot study for long-term carbon monitoring projects in the arid areas of Namibia and as a carbon baseline in the ProNamib.

Description

Thesis submitted in fulfillment/partial fulfillment of the requirements for the degree of Master of Natural Resources Management at the Namibia University of Science and Technology.

Keywords

Drylands, Carbon stock, Habitats, Management units, ProNamib Nature Reserve, Allometric equations

Citation

Pius, E.T. (2023). Assessment of the Carbon Pool at ProNamib Nature Reserve (PNNR) [Unpublished Master's Thesis]. Namibia University of Science and Technology.